Preclinical Study of a Minimally Invasive Cochlear Implant Device Based on 3D Printing of a Custom Guide.

Objective: The aim of this study is to test the feasibility of a custom 3D-printed guide for performing a minimally invasive cochleostomy for cochlear implantation.

Study Design: Prospective performance study.

Setting: Secondary care.

Surgical training strategies for physicians practicing in an isolated environment: an example from Antarctica. International survey of 13 countries with active winter stations.

For 60 years, human presence in Antarctica has required particularly demanding medical skills. Nevertheless, the preparation of physicians working in this extreme environment remains unknown and deserves clarification. This study aimed to summarise data on the surgical training given to physicians by different countries.

Surgical epidemiology of Antarctic stations from 1904 to 2022: A scoping review.

In Antarctica, it is extremely difficult to organise medical evacuations in winter. Antarctic physicians are often alone and must be prepared to perform surgery and dentistry, even if they are not specialists. This scoping review summarises epidemiological data on the types of surgical procedures performed in Antarctica and identifies gaps in the literature in this area.

Radiological relationship of the ethmoid slit with the frontal sinus and the anterior ethmoidal artery and applications to the frontal sinus drillout.

Purpose: To compare two types of CT acquisition parameters: CT scan of the facial bone and CT scan of the sinuses, for studying the ethmoidal slit and its relationship with the frontal sinus and anterior ethmoidal artery.

Materials And Methods: Retrospective study of 145 scans of the sinuses and 79 of the facial bones performed between 2012 and 2016. On each scan, the visibility of the ethmoidal slits, their length, their distance from the ethmoidal artery, and their relationship with the anterior and posterior wall of the frontal sinus were studied.

The advantages of modified Thiel technique in head and neck surgical anatomy teaching.

Purpose: Thiel's body preservation method allows the donor body to retain color and soft tissue that are similar to those of a living individual. Since its initial description, the technique has not been developed much. Here, we propose a simpler protocol applied to the head and neck, making the technique easier, cheaper, and more accessible to a greater number of medical schools.

Motion Sickness Lessons from the Southern Ocean.

The objectives were to assess the prevalence, severity, and medication taken, and to look for predictive factors in order to better identify characteristics of passengers at risk of motion sickness during transport from Hobart in Tasmania to the French polar stations in Antarctica. There were 239 passengers who were surveyed over 4 yr with 4 round trips per year using the Motion Sickness Susceptibility Questionnaire (MSSQ), Simulator Sickness Questionnaire (SSQ), state-trait anxiety test (STAI-Trait and STAI-State), and general parameters (age, gender, number of trips, jet-lag, direction of the trip), medication, calculation of the distance of each passengers cabin to the center of gravity (CoG). While the passengers had a low intrinsic sensitivity to motion sickness (MSSQ), 94 reported at least one SSQ symptom of motion sickness, and 38 vomited.

Impaired Attentional Processing During Parabolic Flight.

Previous studies suggest that altered gravity levels during parabolic flight maneuvers affect spatial updating. Little is known about the impact of the experimental setting and psychological stressors associated with parabolic flight experiments on attentional processes. To address this gap, we investigated the level of alertness, selective and sustained attention in 1 and 0 g using a Go/No-Go Continuous Performance Task.

Stratification of hippocampal electrophysiological activation evoked by selective electrical stimulation of different angular and linear acceleration sensors in the rat peripheral vestibular system.

It has become well established that vestibular information is important for hippocampal function and spatial memory. However, as yet, relatively little is known about how different kinds of vestibular information are 'represented' in different parts of the hippocampus. This study used selective electrical stimulation of each of the 5 vestibular sensors (the horizontal (HC), anterior (AC) and posterior (PC) semi-circular canals, and the utricle and saccule) in the rat and recorded local field potentials (LFPs) across the hippocampus, using a 16 electrode microarray.

The effects of selective electrical stimulation of the rat cochlea on hippocampal field potentials.

The hippocampus is a brain structure well known for its importance to spatial learning and memory. As such it is assumed to use multisensory integration in order to generate mathematical maps of the spatial environment. Auditory inputs to the hippocampus have been described to a limited extent.

New landmarks in endonasal surgery: from nasal bone to anterior cribriform plate including branches of anterior ethmoidal artery and nerve and terminal nerve.

Background: Despite the development of anterior skull base surgery, the anatomy of the nasal bone and anterior cribriform plate remains unclear. A recent study confirmed 2 distinct foramina in the anterior part of cribriform plate: the ethmoidal slit (ES) and the cribroethmoidal foramen (CF). The aim of this study was to specify their content, their anatomic relationship to the frontal sinus and skull base, and their potential value in skull base surgery.

New detailed description of the anterior part of the cribriform plate using anatomic specimens and computed tomography.

Purpose: Ethmoidal slit (ES) and cribroethmoidal foramen (CF) have been poorly studied, without any radiological description. They may ease cribriform plate's diseases. The objective was to describe the frequency, size, and computed tomography (CT) appearance of these foramina.

The balance of sleep: Role of the vestibular sensory system.

The vestibular system encodes linear and angular head motion supporting numerous functions from gaze stabilization and postural control, to high-level cortical functions involving spatial cognition, including self-body perception, verticality perception, orientation, navigation and spatial memory. At the brainstem and mesencephalic levels, the vestibular organs also influence postural blood pressure regulation, bone density and muscle composition via specific vestibulo-sympathetic efferences and have been shown to act as a powerful synchronizer of circadian rhythms. Here, we review the evidence that sleep deprivation and sleep apnea syndrome alter vestibular-related oculo-motor and postural control, and that, in turn, vestibular pathologies induce sleep disturbances.

Vestibular-related eye movements in the rat following selective electrical stimulation of the vestibular sensors.

Rats are the most commonly used species in the neurosciences; however, little is known about the effects of selective electrical stimulation of individual vestibular sensors, on their eye movements. This limits their use to study the effects of vestibular stimulation on the brain, and their use in further exploring novel technologies such as artificial vestibular implants. We describe the effects of electrical stimulation of each vestibular sensor on vestibular-related eye movement in rats and compared the results to other species.

Differential regulation of NMDA receptor-expressing neurons in the rat hippocampus and striatum following bilateral vestibular loss demonstrated using flow cytometry.

There is substantial evidence that loss of vestibular function impairs spatial learning and memory related to hippocampal (HPC) function, as well as increasing evidence that striatal (Str) plasticity is also implicated. Since the N-methyl-d-aspartate (NMDA) subtype of glutamate receptor is considered essential to spatial memory, previous studies have investigated whether the expression of HPC NMDA receptors changes following vestibular loss; however, the results have been contradictory. Here we used a novel flow cytometric method to quantify the number of neurons expressing NMDA receptors in the HPC and Str following bilateral vestibular loss (BVL) in rats.

Effects of electrical stimulation of the rat vestibular labyrinth on c-Fos expression in the hippocampus.

Several studies have demonstrated that electrical activation of the peripheral vestibular system can evoke field potential, multi-unit neuronal activity and acetylcholine release in the hippocampus (HPC). However, no study to date has employed the immediate early gene protein, c-Fos, to investigate the distribution of activation of cells in the HPC following electrical stimulation of the vestibular system. We found that vestibular stimulation increased the number of animals expressing c-Fos in the dorsal HPC compared to sham control rats (P ≤ 0.

Extended endonasal approach versus maxillary swing approach to the parapharyngeal space.

Background: The nasopharyngeal and parapharyngeal spaces are difficult for surgeons to access. Of the various external routes described, the maxillary swing has emerged as the gold standard because of its simplicity. However, its morbidity has led to the development of less invasive techniques.

Anatomy and surgical approach of rat's vestibular sensors and nerves.

Background: The rat is one of the most used species in the neurosciences, but how to selectively reach each of its 5 vestibular sensors has never been described. Besides, new functions of the vestibular system have been recently discovered in the rat involving vegetative, circadian and cognitive functions. But the central pathways sustaining these functions and the role of each of the vestibular sensors are not clear.

What vestibular tests to choose in symptomatic patients after a cochlear implant? A systematic review and meta-analysis.

Vestibular function after cochlear implantation is difficult to understand, as subjective vestibular symptoms seem uncorrelated with the results of objective tests. Consequently, clinicians may struggle to decide what assessments to perform for a symptomatic patient. We used a systematic review and meta-analysis approach to enlighten this point.